Bicycle frame



FIG. 1 is a perspective view of a bicycle frame showing our new design, wherein the unclaimed portions are shown in dashed broken lines;

FIG. 2 is a side view thereof;

FIG. 3 is a side view opposite the side shown in FIG. 2;

FIG. 4 is a front view thereof;

FIG. 5 is a rear view thereof;

FIG. 6 is a top view thereof; and,

FIG. 7 is a bottom view thereof.

Throughout the figures, the dashed broken lines show unclaimed portions of the bicycle frame and form no part of the claimed design. 

The ornamental design for a bicycle frame, as shown and described. 